diff --git a/test cases/unit/17 prebuilt shared/patron.c b/test cases/unit/17 prebuilt shared/patron.c
index 82d9678aa..461d7b487 100644
--- a/test cases/unit/17 prebuilt shared/patron.c	
+++ b/test cases/unit/17 prebuilt shared/patron.c	
@@ -5,4 +5,5 @@ int main(int argc, char **argv) {
     printf("You are standing outside the Great Library of Alexandria.\n");
     printf("You decide to go inside.\n\n");
     alexandria_visit();
+    return 0;
 }